Internal combustion engine



Dec. 22, 1942. G. J. LESER INTERNAL COMBUSTION ENGINE Filed March 19, 1941 INVENTOR I 2' J Leser Glenv ATTORNEYS Patented Dec. 22, 1942 UNITED STATES TENT OFFICE 2,306,217 INTERNAL {COMBUSTION ENGINE Glen J. Leser, Sandusky, Ohio Application March 19, 1941, Serial No. 384,115

Claims.

This invention relates to positive injection type engines, and in particular to a four-cycle, internal combustion engine employing a volatile fuel, such as gasoline, fuel oil, and the like, and obtaining its power from the pressure derived from the combustion of such fuel.

It is an object of the present invention to provide an internal combustion engine in which the combustion supporting fluid is injected under pressure into the combustion chamber to insure the presence of a full charge each time combustion takes place, and to do away with any losses occasioned by the so-called suction stroke of the ordinary four-cycle, internal combustion engine.

Another object is to provide an engine which is capable of operating at high speeds to deliver increased power, but which does not require a corresponding increase in size and weight. Such an engine is especially useful in the marine and aircraft engine fields, as well as for automotive or other applications.

A further object is to provide a high speed internal combustion engine which will deliver increased power per unit of size and weight.

A still further object is to provide an internal combustion engine which is compact, simple in design and construction, and which does not require too radical a departure from the principles of internal combustion engine construction as known at the present time.

Other objects and advantages of the present invention will become apparent from the following detailed description, accompanied by the drawing, in which like parts throughout the various views are indicated by the same reference numerals.

In the drawing:

Figure 1 is an end elevational View, with parts broken away, showing a single cylinder engine embodying the present invention; and

Fig. 2 is a sectional view taken substantially on line 2-2 of Fig. 1, and illustrating details of the structure of the invention shown in Fig. 1.

While a single cylinder engine has been shown in the drawing, it is obvious that the present invention may be incorporated in engines having two or more cylinders. Also, it may be noted that the present invention may be adapted to either gasoline or Diesel-type engines, but the gasoline type has been arbitrarily chosen for purposes of description and illustration.

In the form of the invention shown in the draw ing, the positive injection is obtained briefly by the use of a composite piston reciprocating in a cylinder having two concentric bores of different diameter, one of the bores acting as a combustion and explosion cylinder, and the other bore acting as a pumping or compressor cylinder.

Figs. 1 and 2 show a simple form of invention in which a crankshaft is indicated by the numeral I and a flywheel by the numeral 2, the crankshaft being disposed within a suitable crankcase 3. Above the crankcase and secured thereto is a cylinder block 1.! having a combustion or explosion cylinder 5 formed therein. A pumping or compressor cylinder fi is disposed beneath the combustion cylinder and concentric therewith, the diameter of the cylinder I5 being larger than that of the cylinder 5. A composite piston, indicated generally by the numeral 1, is mounted within the cylinders and is connected to a crank of the crankshaft I by a suitable connecting rod 8. An upper or head portion I!) of the piston I is slidingly mounted for closely fitting reciprocation within the cylinder 5 and may be provided with circumferential ring grooves to accommodate piston rings, as desired. At the lower or skirt portion of the piston 1 is provided an enlarged portion I I for closely fitting reciprocation within the cylinder 6. The portion II may also be suitably grooved for the accommodation of piston rings.

Suitably secured to the cylinder block 4 at the top thereof is a cylinder head I2 in which are slidingly mounted intake and exhaust valves I3 and I4, respectively, which admit and discharge the combustion supporting fluid to the combustion chamber in the cylinder 5. These valves are of the overhead type, being disposed with their heads downward, and each of their upturned stem ends is connected to one end of a rocker arm I5. Both of the rocker arms I5 are pivotally mounted to a boss I6 carried by and projecting from the cylinder head I 2 (Fig. 1). The opposite end of each of the rocker arms I5 is connected to a push rod I1, which extends down the side of the,en-' gine and is received in a tappet I8 slidingly mounted in a portion of the cylinder block. Each tappet and. push rod is actuated by a suitable cam 20 which is fixed to a rotatable cam shaft 2 I. The cam shaft ZI may be geared to and driven by'the crankshaft by suitable gears 22.

Threadedly mounted in the cylinder head and connected to a suitable electrical circuit (not shown) is a spark plug 23, which may be used to ignite the fuel and air mixture in the combustion chamber. Before the fuel and air mixture is fed to the combustion chamber, it is compressed in the cylinder 6 by the enlarged piston portion II. The fuel and air are mixed in a suitable carburetor (not shown), from which the mixture is;

conducted to the cylinder 8 through a suitable tube or passage 24 (Fig. 1) An inlet port 25 of the cylinder 6 is disposed at the top thereof, extending through the wall of the block A, and is alternately placed in and out of communication with the passage 24 by a rotary valve 26. The valve 26 is opened each time the enlarged portion I I of the piston is at top dead center of its stroke and is beginning its downward movement. This valve closes approximately when the piston portion I I is at bottom dead center, and as the portion II begins its upward stroke the air and fuel mixture is compressed and expelled from the cylinder 6 through a discharge port 21, which is controlled by a rotary valve 28 similar to the valve 26 and rotated in timed relation thereto. The rotary valve 23 is open during the upward movement of the portion II from bottom dead center to top dead center. The mixture passes through the valve 28 into a tube 30, which leads to a suitable reservoir or storage chamber 3|. If desired, the entrance to the reservoir SI may be controlled by a check valve, shown in the drawings as an ordinary spring pressed poppet valve 32.

The reservoir 3I communicates with the cornbustion chamber through a suitable tube 33, the entrance of the air and fuel mixture to the combustion chamber from the tube 33 being controlled by the intake valve I3. After combustion, the exhaust gases are expelled from the combustion chamber to a discharge or exhaust tube 36, which is disposed directly behind the intake tube 33 when looking in the direction of Fig. 1. The discharge of exhaust gases is controlled by the exhaust valve I4.

The rotary valves 26 and 2B are driven in timed relation with each other and in timed relation with respect to th crankshaft. This may be done by rotating the valves by means of an endless chain or belt 34 carried by three sprockets 35 mounted on the rotary valves and the cam shaft, respectively. Since the rotary valves 26 and 28 are required to rotate only 180 degrees between an open position and the succeeding open position, and since each of these valves opens twice during each two revolutions of the crankshaft, the camshaft may be driven at onehalf the speed of the crankshaft. With the camshaft rotating at half the speed of the crankshaft, the cams to operate the valves I3 and I4 are only required to actuate the push rods I'I once during each rotation of the camshaft or once during each two rotations of the crankshaft.

In the form of the invention shown in the drawing, the volume of the pump or compressor cylinder 6 is approximately equal to half the volume of the reservoir 3I, and the volume of the reservoir 3| is approximately equal to the volume of the combustion chamber. Thus, during each cycle of the engine the pressure in the reservoir will increase from atmospheric pres-- sure in accordance with the work done by the compressor piston II and will decrease to approximately atmospheric pressure after the explosive'mixture has passed from the reservoir to the combustion. chamber.

By providing a positive injection of the fuel and air charge into the combustion chamber it is permissible to construct the valve mechanism, so that the intake valve 53 may be opened at approximately dead center and will remain open for about 180 degrees revolution of the crankshaft, closing at approximately bottom dead center when the piston reverses its path and begins its compression stroke. It is believed preferable that the exhaust valve I4 be opened before bottom center and remain open until a few degrees before top dead center. Of course these timing characteristics may be varied according to the use to which the engine is applied and to the output characteristics desired.

It is to be understood that variations and modifications of the specific devices herein shown and described for purposes of illustration may be made without departing from the spirit of the invention.

What I claim is:

1. In a four-cycle engine, an explosion cylinder, a pumping cylinder disposed concentrically thereof, a, crankshaft, a composite piston connected to the crankshaft and having a portion mounted for reciprocation in the explosion cylinder and a portion disposed for reciprocation in the pump cylinder to compress and expel at each rotation of said crankshaft a charge of combustible and combustion supporting fluid which has been fed to the pump cylinder, valve mechanism for said explosion cylinder to cause injection of a charge of combustion supporting fluid before explosion and expulsion of the burnt fluid after explosion, and separate valve mechanism to cause feeding of a charge of combustion supporting fluid mixture into said pump cylinder and expulsion therefrom, said valve mechanism for the pump cylinder operating twice for each operation of the valve mechanism for the explosion cylinder.

2. A four-cycle, internal combustion engine which comprises a crankshaft, a combustion cylinder with intake and exhaust valves, a compression chamber integral with said combustion cylinder, a piston operably connected to the crankshaft and working in the combustion cylinder, a supplementary portion of said piston working in the compression chamber to draw a charge of fuel and air into. the compression chamber and force it therefrom at each rotation of said crankshaft, a compressed fuel and air reservoir connected to the compression chamber by a passage, inlet and discharge valves for the compression chamber, a passage communicating between the reservoir and the intake valve for the combustion cylinder, actuating means for the intake and discharge valves of the compression chamber causing each of them to open and close once during each rotation of the crankshaft, and actuating means for the intake and exhaust valves of the combustion cylinder causing each of them to open and close once during each two rotations of said crankshaft.

3. A four-cycle internal combustio engine which comprises a crankshaft, a combustion cylinder, a compressing cylinder concentric and integral with said combustion cylinder and disposed between said combustion cylinder and said crankshaft, pistons connected to said crankshaft and mounted for reciprocation in each of said cylinders, means for feeding combustion supporting. fluid and combustible fluid to the compressing cylinder and for discharging the fluid therefrom at each rotation of said crankshaft, a reservoir for containin fluid under pressure discharged from the compressing cylinder, means for feeding fluid from the reservoir to the combustion cylinder and exhausting burnt combustion fluid therefrom, the fluid pressure in said reservoir increasing from approximately atmospheric pressure and decreasing to about atmospheric pressure once duing each two rotations of said crankshaft.

4. A four-cycle internal combustion engine which comprises a crankshaft, a combustion cylinder, a compression cylinder, a piston connected to said crankshaft for reciprocation in both of said cylinders, valve mechanisms for each of the cylinders to permit the intake of air and combustible fluids and expulsion of fluids therefrom at each rotation of said crankshaft, a reservoir connected in series with the exhaust of the compression cylinder and the intake of the combustion cylinder, a check valve to maintain fluid from the compressor cylinder in said reservoir, and valve actuating means for each of the valve mechanisms, said actuating means causing the valve mechanism of the compressor cylinder to operate twice for each operation of the valve mechanism for the combustion cylinder.

5. A four-cycle internal combustion engine comprising a combustion cylinder, intake and exhaust means for said combustion cylinder, a compression cylinder, intake means for intake of air and combustible fluid to said compression cylinder, exhaust means for said compression cylinder, a composite piston having portions mounted for reciprocation in each of said cylinders, a reservoir mounted in series with the exhaust of the compression cylinder and the intake of the combustion cylinder, actuating means to operate the intake and exhaust means of the combustion cylinder once during each cycle, and actuating means to operate the intake and exhaust means of the compression cylinder twice during each complete cycle, whereby combustible fluid is compressed into said reservoir at each rotation of the crankshaft.

6. A four-cycle internal combustion engine which comprises a crankshaft, a combustion cylinder, a compression cylinder, a piston connected to the crankshaft for reciprocation in the combustion cylinder, a supplementary integral portion of said piston operating in the compression cylinder, valve mechanism for the compression cylinder to permit intake of a charge of combustion supporting fluid and combustible fluid and exhaust of the compressed charge, valve mechanism for the combustion cylinder to permit intake of a compressed charge and exhaust of burnt gases, a reservoir connected in series with the exhaust of the compression cylinder and the intake of the combustion cylinder, the volume of said reservoir being approximately equal to the volume of the combustion cylinder and approximately twice the volume of the compression cylinder, valve actuating means to operate the valve mechanism of the combustion cylinder once dur ing each cycle of the engine, and other valve actuating means for operating the valve mechanism of the compression cylinder twice during each cycle of the engine.

'7. A four-cycle internal combustion engine comprising a compression cylinder, a combustion cylinder, a composite piston having portions mounted for reciprocation in each of said cylinders, a reservoir, means for feeding a charge of combustion supporting fluid and combustible fluid to the compression cylinder and for exhausting the compressed charge to the reservoir, means for feeding a compressed charge from the reservoir to the combustion cylinder and for exhausting burnt combustion gases therefrom, and means for causing the feeding and exhaust means for the compression cylinder to operate twice for each operation of the feeding and exhaust means of the combustion cylinder, whereby said combustibie fluid is compressed into said reservoir at each rotation of the crankshaft.

8. A four-cycle internal combustion engine which comprises a crankshaft, a combustion cylinder having an intake and an exhaust valve, a compression cylinder having an intake for combustible fluid and an exhaust valve, a composite piston connected to said crankshaft and having portions mounted for reciprocation in each of said cylinders, a reservoir connected in series with the exhaust of the compression cylinder and the intake of the combustion cylinder, a shaft driven from the crankshaft at one half the speed of the crankshaft, means associated with the driven shaft for operating each of the valves of the combustion cylinder once during each rotation of said shaft, and means for operating each of the valves of the compression cylinder twice during each rotation of said shaft, whereby combustible fluid is compressed and forced into said reservoir at each rotation of said crankshaft.

9. A four-cycle engine which comprises a combustion cylinder, a concentric pumping cylinder, a piston mounted for reciprocation in both of said cylinders, a reservoir for containing fluids discharged from said pumping cylinder, means for feeding combustible fluid and combustion supporting fluid to the pumping cylinder, means for discharging the fluid therefrom and into said reservoir at each rotation of the crankshaft, means for feeding fluid from said reservoir to said combustion cylinder only once every two rotations of said crankshaft, and means for exhausting burnt combustion fluid, said pumping cylinder operating to force compressed fluid into said reservoir twice for each explosion in said combustion cylinder, substantially all of said fluid compressed into said reservoir being fed into said combustion cylinder.

10. In a four-cycle engine an explosion cylinder, a pumping cylinder disposed concentricallythereof, a crankshaft, a composite piston connected to the crankshaft and having a portion mounted for reciprocation in the explosion cylin der and another portion of larger diameter than said first-mentioned portion for reciprocation in said pumping cylinder to compress and expel at each rotation of the crankshaft a charge of combustible and combustion supporting fluid which has been fed to the pump cylinder, valve mechanism for said explosion cylinder to cause injection of a charge of combustion supporting fluid before explosion and to cause expulsion of the burnt fluid after explosion, and separate valve mechanism to cause feeding of a charge of combustion supporting fluid into said pump cylinder and expulsion therefrom, said valve mechanism for said pump cylinder operating twice for each operation of the valve mechanism for the explosion cylinder.

GLEN J. LESER. 

